title: Age-Related Changes of Serum Soluble Interleukin 9 Receptor (sIL-9Rα) in Healthy Subjects.
abstract: Most cytokine receptors including interleukin (IL)-9 have soluble counterparts in body fluids. We planned to investigate the pathophysiological significance of the serum soluble IL-9 receptor (sIL-9R) level. We determined the serum sIL-9Rα chain (sIL-9Rα) levels in 96 healthy Japanese individuals to establish a control value by means of specific human sIL-9Rα ELISA, followed by a preliminary application in a patient with diarrhea positive hemolytic uremic syndrome. Age was negatively correlated with the sIL-9Rα level (Spearman r = -0.241, n = 96, p = 0.0180). The serum sIL-9Rα level showed a progressive decline to the normal adult level by the age of 30. The serum sIL-9Rα level of the patient with HUS was markedly higher than those of the age-matched control from the onset of the disease. Because of the remarkable age-dependent variability of sIL-9Rα in healthy subjects, disease-related changes, as well as therapy-dependent alterations, should be considered with caution. Thus, it is recommended that when the serum sIL-9Rα levels of patients are evaluated, the values should be compared with those of age-matched controls. The established control value will be used to discriminate between normal and the pathological conditions in our future studies.
authors.affiliation: Laboratory of Immunology and Microbiology, Faculty of Pharmacy, Chiba Institute of Science, 3 Shiomi-cho, Choshi, Chiba 288-0025 Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Mayuri
authors.initials: M
authors.lastname: Tanaka
authors.forename: Asami
authors.initials: A
authors.lastname: Kasahara
authors.forename: Takazumi
authors.initials: T
authors.lastname: Hara
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Gotoh
authors.forename: Naoya
authors.initials: N
authors.lastname: Fujita
authors.forename: Takashi
authors.initials: T
authors.lastname: Fukui
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Masuzawa
keywords: ELISA; Hemolytic uremic syndrome (HUS); Soluble interleukin 9 receptor α chain (sIL-9Rα)